The protein kinase, maternal embryonic leucine zipper kinase (MELK), is known to be involved in regulating cell cycle progression, cellular proliferation, apoptosis, and mRNA splicing (Badouel et al. (2006) Cell Cycle 5:883-889 and Badouel et al. (2010) Exp. Cell Res. 316:2166-2173). MELK has also been identified using gene expression profile analyses to be associated with a number of cancers, including breast, lung, bladder, lymphoma, and cervical cancer cells and mammary tumor formation in animal models (Komatsu et al. (2013) Int. J. Oncol. 42:478-506; Pickard et al. (2009) Breast Cancer Res. 11:R60; Hebbard et al. (2010) Cancer Res. 70:8863-8873; Lin et al. (2007) Breast Cancer Res. 9:R17; WO 2004/031413; WO 2007/7013665; and WO 2006/085684). Despite this association, however, functional analyses of MELK-mediated oncogenesis have not been performed to date and the mechanisms of MELK-mediated oncogenesis and, by extension, assays for determining agents useful in regulating such oncogenesis, are not known. This lack of understanding has prevented the identification of biomarkers that reliably report MELK enzymatic and/or oncogenic activity. While certain MELK-targeting inhibitors of kinase activity are known (see, for example, Chung et al. (2012) Oncotarget 3:1629-1640), there is a clear need in the art to identify biomarkers of MELK-mediated oncogenesis in order to provide rapid and effective means for evaluating MELK-targeted anti-cancer therapies.